1999 Gmc Yukon Electric help

[BradyBargo]

Good Evening everyone I have a 1999 gmc Yukon has a power drain over night things I’ve noticed
-Rear HVAC Fuse blows threw the night
Nothing is wrong with rear hvac blower motor everything is functioning correctly

-Power Door Lock, Six-Way Power Seat, Keyless Entry Module Breaker gets so hot can’t touch it in about a hour and seats stop working cause breaker gets hot and kicks out

Any help where to start at would be nice just purchased this thing would like to get everything fixed

When I purchased this thing I had to put a ecm on it got it from a same year Yukon and also had to put the passlock module in it to

 

[blondie70]

Don't know what's wrong with it...but...I think I would be unhooking the battery at nite or whenever you leave it unattended. Do this until you get the problems resolved. Don't wanna burn that baby down !

 

[GMCChevy]

Maybe there's a stuck or bad button somewhere causing something that module controls to work constantly. Or that module is bad?

 

[BradyBargo]

Don't know what's wrong with it...but...I think I would be unhooking the battery at nite or whenever you leave it unattended. Do this until you get the problems resolved. Don't wanna burn that baby down !

Yeah that’s what I’ve been doing

 

[BradyBargo]

Maybe there's a stuck or bad button somewhere causing something that module controls to work constantly. Or that module is bad?

Just sucks trying to chase something like this down lol

 

[exp500]

If you are drawing anything over about 100 Ma you should be able to find the circuit by removing fuse or relay for the draw. Use the test points on top of fuses to make test easier. Circuit dagrams in manual.
If you have a short or failed component, it is possible/probable for a backfeed of power connecting more than one fused system or component.
When you get to the point that you can stop the draw by removing fuse or relay, or at least know which power lead it is on then repair is pretty much follow the wires.
Report back here with findings and many folks will step up with helpful suggestions.

look here- https://www.gmt400.com/threads/88-95-service-manuals.43575/

 

[NoReverseYukon]

Just by knowing how much dog hair, dirt, et cetera collects under my front seats, I would start with taking a look under yours. There might be stuff under there causing an intermittent short.

 

[BradyBargo]

Just by knowing how much dog hair, dirt, et cetera collects under my front seats, I would start with taking a look under yours. There might be stuff under there causing an intermittent short.

Checked under them from what I seen everything looked great and the passenger seat don’t work at all don’t know why none of the functions, so I maybe thought that is what was keeping the 30amp breaker hot so I unplugged the seat made no difference don’t know why the seat doesn’t work no way all the motors on it failed at one time

 

[BradyBargo]

Update guys was driving down there road here in the dark and notice my interior lights flashed and I heard a fuse pop and it was to my rear hvac I kept wondering what was blowing the fuse to the rear hvac so how is the interior lights even near the same circuit

 

[NoReverseYukon]

With seemingly unrelated circuits causing problems, I would suggest you check the main interior wiring harness. You probably have one or more wires making contact with the body(ground). Electrical problems suck.

 

[BradyBargo]

the interior lights that’s activated by door when open
Do they get power from the 30 amp breaker I’m listing above cause they don’t work without it in I’m just trying to figure out where these problems are and what to chase on the fuse panel diagram I don’t see where it states it controls the door lock control module

 

[BradyBargo]

With seemingly unrelated circuits causing problems, I would suggest you check the main interior wiring harness. You probably have one or more wires making contact with the body(ground). Electrical problems suck.

Are you referring to the one behind glovebox or under steering Column

 

[NoReverseYukon]

Are you referring to the one behind glovebox or under steering Column

I have a NBS (2001) so I am just about at the end of the suggestions I can offer on your OBS. But I would think that you have some wires running along the side under the door jamb trim piece or under the carpet. Those wires are what sends power to the seats ( 1 of original problems ). Good luck, but I'm gonna tap out now.

 

[exp500]

Post the manual diagram page you are working from, then we can walk you thru the most likely steps for a proper diagnosis/ repair. May be 3 or more pages each showing the components you have mentioned. A failed relay can move in many directions because some fused some unfused as you have noticed.

 

[BradyBargo]

Hello guys haven’t touched this thing since I made this thread another thing going on when I speak of interior lights none of the 4 lights on the doors even come on wonder if I have a issue there? Causing other issues

 

[Fless]

You can get wiring diagrams from https://charm.li/ and use those to determine what the fused circuits feed. That will help you narrow it down.

 

[GMCChevy]

It's probably all related. You still need to to check that circuit and see what alls on it as a start to figuring it out.